In recent times, in-line-type roller skates have become extremely popular. This type of roller skate is commonly identified as a ROLLERBLADE skate (ROLLERBLADE being a trademark of Rollerblade, Inc.) and is characterized by having three or more linearly-aligned wheels centrally located beneath each skate. The wheels are usually adjustably secured to a rigid undercarriage or frame that is fastened to the bottom portion of the shoe portion of the skate.
In-line roller skates suffer from a problem that has plagued roller skates since their inception. Namely, a roller skate is extremely unstable when the user has to walk on an uneven or irregular surface while wearing the skates. For example, when a user goes up or down stairs, he or she will normally tightly hold onto a handrail, if available, since the skates may inadvertently roll on the stair treads. Similar problems are encountered when skates are worn while walking on slippery surfaces in which, for example, a loose covering such as sand is present.
A number of other problems are also experienced with roller skates when they are worn while traversing certain types of surfaces. For example, some surfaces can be easily marked by the roller skate's wheels and therefore the user must remove his or her skates prior to stepping on the surface. Another example is when the surface can be damaged by the high forces exerted by the wheels of the skates due to their small contact area. This can cause carpeting to be torn or tiles to be irreparably dented.
In the prior art, a number of skate accessories have been developed in an attempt to overcome the above noted problems. For example, in 1880, Gibbs received patent No. 30,627 for a wooden member that had a top-located groove sized to receive the runner of an ice skate. In endeavors more particularly adapted to roller skates, Dolce (Pat No. 3,861,697), Loredo (Pat. No. 4,413,842), Melendez (Pat. No. 4,364,187) and Famolare, Jr. have all invented members that are removably secured to the bottom of a roller skate. However, all of the prior art deals with apparatus specifically designed for roller skates that have tandem wheels. None of the prior art is suitable for in-line roller skates. In addition, all of the prior art devices are bulky, complicated in design, relatively heavy and are time consuming to install.